Interactions between Trypanosoma brucei and CD8+ T cells.

The mechanisms for several important features o f African trypanosomiasis are still largely unexplained. These include (1) the occurrence of parasite growth-promoting molecules provided by the host, (2) polyclonal T- and B-cell activation and the development of immunosuppression and (3) neuropsychiatric signs. Here Tomas Olsson, Moiz Bakhiet and Krister Kristensson focus on interactive events between Trypanosoma brucei and CD8(+) T cells, and the release of a diffusible molecule from T. brucei that triggers CD8(+) T cells to produce interferon-gamma (IFN-gamma). This cytokine provides a growth stimulus for the parasite and modulates events in the host's immune and nervous systems.